Dynamics of Substrate Utilization Pattern in Red Soils: An Indicator of Soil Quality Changes

A laboratory experiment was conducted to evaluate the effect of different land uses, soil fertility and environmental quality on substrate utilization patterns. Multivariate analysis of Biolog sole carbon source utilization tests demonstrated that land use history and plant cover type had a significant impact on microbial community structure. However, there was no systematic change in microbial community structure associated with increased organic matter or microbial biomass. Microorganisms were sensitive to environmental change. Addition of Cu to three red soils (short-term cultivated red sandy soil, mid-term cultivated red clayey soil, and long-term cultivated red clayey soil) at a rate of 500mg kg−1 resulted in a lower utilization rate for 21 carbon sources. In addition, microbial community structure in the long-term cultivated red clayey soil was significantly altered by Cu addition at the rate of 500 mg kg−1.